Array flat() and flatMap()
Widely available since 2022-07-15
The flat() and flatMap() methods for arrays creates a new array such that each nested array item is concatenated into it.
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Specifications
- ECMAScript® 2026 Language Specification (#sec-array.prototype.flat), from TC39 (Ecma International).
- ECMAScript® 2026 Language Specification (#sec-array.prototype.flatmap), from TC39 (Ecma International).
Browser support (view on caniuse.com)
- Chrome 69 Released on 2018-09-04
- Chrome Android 69 Released on 2018-09-04
- Edge 79 Released on 2020-01-15
- Firefox 62 Released on 2018-09-05
- Firefox for Android 62 Released on 2018-09-05
- Safari 12 Released on 2018-09-17
- Safari on iOS 12 Released on 2018-09-17
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